Brown Spots on Lawn
My lawn was in great shape until this past week when I noticed several brown patches as noted in this picture. I thought I had moles but I poked around with a hand shovel and didn't detect any tunnels or mounds. I have not put down any weed or pest killer. The area does get some water and takes a while to drain but that has been an ongoing issue. This latest problem is perplexing. Any thoughts? Thank you.
Some reasons for the brown spots may be planting the wrong turfgrass species, poor soils, poor drainage, close mowing, etc. We cannot say for sure. See our website for more information http://extension.umd.edu/hgic/cultural-environmental-problems-lawns
We do not have enough information how the turf has been managed. Turf type tall fescue is the recommended grass species and grows best in full sun to part shade. If you planted a contractors mix of different species at some point, some of the grasses may be dying out. such as annual bluegrass, perennial, or annual rye grass. Also, Some grass species can go dormant at different rates during hot, dry weather.
Poor soils - not enough organic matter in the soils to promote root growth, or close mowing, etc. If the area continues to b have poor drainage, then you may want to consider this area for a rain garden.
If you have not had your soil tested within the last several years, it is recommended. Results give pH, liming, and nutrient deficiencies. See our soil testing information http://extension.umd.edu/hgic/soils/soil-testing
All you can do is monitor this area, check drainage, mow to the proper height, and reseed in the fall. See our publication on Lawn Establishment, and Overseeding and our publication on turfgrass maintenance